You will also need the mounting plate. It bolts to the frame of the ATV & has ears for the push tubes to attach to. I'm not sure about the winch kit you mentioned. If you already have a winch, all you have to do is make sure you have the roller fairlead to save your winch cable. I also put a hook with a safety catch on the end of the winch cable to keep the cable from falling off the pushtube when the cable was let out.

I would imagine that a 375 or 400 would still push snow pretty good. I was more worried about traction than power, but my 500 hooked up real good while plowing. I'd imagine that either of the 2 you are looking at will also. The Auto sure makes it nice though.

 

Im just going to put it in a trailer that I have. The only reason I need a trailer is because when I go up to my cabin it, will be nice to be able to plow the driveway, the driveways that I am going to plow, i can just drive it down the road.
Thanks

 

jburglund, I have a Suzuki King Quad, '99. Stock tires did fine for plowing snow sitting on top the little 280cc. engine. Don't even have to go to four wheel lock to get most jobs done. I'm sure which ever you pick will be more than enough power. You will need traction but remember, you're only going to push so much snow before weight transfer is overcome.
Stitch, I don't think you want to go to a 60" plow to push snow in your part of the country. If you only go to the other house once in a while, snow will probably be more than your quad can handle during the peak season of snow. I find it easier to call ahead and have the locals plow with the truck before I get there. That way, if there's six to eight inches back on the ground when I get there, the quad can take care of it. I'm sure either will do the job but the 50 inch should do more work for you in the 10 to 24 inches of snow, that I think you may see.
Chuck